1. Field
Disclosed herein are to a superconducting composite, a preliminary product of a superconducting composite and method for producing same.
2. Description of Related Art
Various types of superconductors that can be produced on a large scale are known. NbTi alloys and intermetallic Nb3Sn compounds exhibit a transition temperature Tc of less than 20 K and can be produced in large strands by means of classic shaping methods such as extruding, thermoforming, or rolling. However, the low transition temperature leads to high equipment and cooling costs.
Superconducting copper oxide-based compounds, e.g. YBCO (Tc approximately 92 K), Bi-2212 and Bi-2223 with a transition temperature of approximately 110 K and T1-2223 (Tc approximately 125 K) are also known. These superconductors are referred to as high-temperature superconductors (HTS″). The electronic properties of the HTS are characterized by the two-dimensional cross-linking of the CuO2 planes. The two-dimensional character of the CuO2 conductor planes is reflected in the extreme anisotropic physical properties. In particular, the critical current density Jc in the conductors is strongly determined by the field direction of a distinctive magnetic field.
The superconducting MgB2 phase and the MgB2-based superconducting phases have a transition temperature of up to 40 K. Compared to the textured, copper-based technical conductors, MgB2 conductors display no distinctive anisotropy of the electrical properties in the distinctive magnetic field.
The disadvantage of the MgB2 phase, however, is that it shows little or no ability to be shaped using the classic shaping methods such as rolling, thermoforming or extruding. Producing large conductor strands with homogenous conductor properties for power engineering by means of classic wire manufacturing methods is not easy.